Acurácia de pontos de corte de IMC e circunferência da cintura para a predição de obesidade em idosos

Abstract

Resumo O objetivo deste estudo foi analisar a validade e a acurácia do Índice de Massa Corporal (IMC) e da Circunferência da Cintura (CC) na avaliação de obesidade avaliada pelo excesso de gordura corporal (GC) e propor pontos de corte mais adequados para idosos. Os pontos propostos da literatura IMC (25,27 ou 30 kg/m2) e CC (≥ 102 cm-homens e ≥ 88 cm-mulheres ou ≥ 90 cm-homens e ≥ 80 cm-mulheres) foram avaliados conforme densitometria corporal total. A elevada GC foi definida por percentil > 90. Dos 132 idosos, 60,6% eram mulheres de 60-91 anos. Os pontos de corte recomendados de IMC ≥ 25 e ≥ 27kg/m2 apresentaram desempenhos similares, sendo que o IMC ≥ 30kg/m2 apresentou alta especificidade e baixa sensibilidade no sexo masculino e melhor desempenho para GC nas mulheres. Os pontos de corte convencionais de CC não apresentaram boa sensibilidade/especificidade. Foram propostos novos pontos de corte para IMC (masculino-25 kg/m2; feminino-26,6 kg/m2) e CC (masculino-98,8 cm; feminino-77,8 cm). Estes valores demonstraram sensibilidade e especificidade > 74% e acurácia > 76%. As áreas sob a curva foram > 0,86. O presente estudo propõe a utilização de pontos de corte mais acurados para diagnóstico de obesidade/GC em idosos, sendo para homens IMC 25kg/m2 e CC de 98,8cm e para mulheres IMC de 26,6kg/m2 e CC de 77,8cm, com melhores níveis de sensibilidade e especificidade.

Pontos de corte da circunferência da cintura e da razão cintura/estatura para excesso de peso: estudo transversal com idosos de sete cidades brasileiras, 2008-2009 *

“…The COPs obtained in this study were between 6.5cm and 11.5cm greater than that recommended by WHO for adult women, and between 1cm less and 3.5cm more than its COP established for adult men, in general. In relation to the COP proposed by Silveira et al, 12 our study identified differences of around 1cm for both men and women, when considering the WC COP resulting from the PAHO criterion. With regard to WHtR, COPs were identified close to the 0.55 found by Corrêa et al 11 in 2008/2009, in a sample that was representative of the Brazilian population (≥60 years), with sociodemographic characteristics similar to those of the elderly people included in our study.…”

“…The COPs detected for WC were higher than those established by WHO for the adult population (males ≥94cm; females ≥80cm). 10 When analyzing a sample of elderly (≥60 years old) SUS service users in Goiânia/GO, Silveira et al 12 proposed a WC COP of 98.8cm for males and 90.5cm for females. The COPs obtained in this study were between 6.5cm and 11.5cm greater than that recommended by WHO for adult women, and between 1cm less and 3.5cm more than its COP established for adult men, in general.…”

“…11 Based on information from a cohort study which began in 2008, researchers proposed a WC COP for diagnosing obesity in elderly people (≥60 years) who used Brazilian National Health System (SUS) services in Goiânia/GO. 12 Despite their relevance, studies in the literature that define specific COPs for the elderly in relation to overweight are rare.…”

Body fat percentage assessment by skinfold equation, bioimpedance and densitometry in older adults

“…Analyses for this study used data from the Elderly Project Goiânia [2,18,[25][26][27], which aims to evaluate the health and nutritional status in older adults aged 60 years and older. It is a cohort study with multistage sampling of non-institutionalized older adults in Goiânia city, capital of the Goiás state, Brazil.…”

“…Individuals with pacemakers or any type of metal adjacent to their body, which was a contra-indication for BIA and DXA examination, and those who were unable to respond to the questionnaire, for reasons such as severe deafness or muteness, were also excluded. A detailed description of the study can be found elsewhere [2,18,[25][26][27].…”